1) Field of the Invention
The present invention relates to a server, which executes processing in response to a request transmitted from a client, and returns the result of the processing to the client.
2) Description of the Related Art
For example, when a client acquires information from a WWW (World Wide Web) server through the Internet, generally, a protocol called HTTP (Hyper Text Transfer Protocol) is used for downloading an HTML (Hyper Text Markup Language) document.
In the above system, a browser of a client transmits a request for processing to a server, the server executes the requested processing, and a result of the processing is returned to the client, and displayed by the browser. That is, processing executed by the client is only the transmission of the request and the display of the result of the processing executed by the server, and most of processing is executed by the server. Therefore, a heavy load is imposed on the server.
Usually, a request is sent from a client to a server when a user manipulates a button which is graphically displayed by a browser on the screen. In the currently prevailing operating systems, various commands are input by double-clicking an icon. Therefore, many users apt to double-click buttons even on the browser screen, due to the habit of double-clicking icons. However, a command is usually input when a button is clicked once on the screen displayed by the browser. Therefore, when a button on the browser screen is double-clicked, two identical commands are transmitted to the server, and the server repeats identical processing twice. Thus, such an unnecessary repeat of identical processing further increases the load imposed on the server, causes delay in processing in the server, and reduces the processing capabilities of the system.
In particular, when the traffic is dense, it takes a long time until a result of processing is displayed after a user requests the processing by manipulating a button. Therefore, users become impatient to see the result of processing, and often click an identical button repeatedly. Such repeated clicking also causes delay in processing in the server.
Further, repeated clicking of an identical button may cause a mismatch between data. For example, when a transmission button is repeatedly manipulated on the screen displayed for member registration, a user may be doubly registered.